Dick, your post made it's way between my answer.
I do not completely agree.
In the old days of giant flight, the only way to get the thrust needed for a big plane was to use a reduction drive. WW1 scale fliers still use the technique that allows them to fly slowly and have more thrust per unit of weight.
It is a trade-off. You trade high rpm low thrust high speed for low rpm, high thrust low speed. The loss of the gear conversion is very much compensated by the gain/increase of flow speed bypass efficiency when your plane needs to fly at pitch speed. Look at it this way. A helicopter needs less power to lift it's weight than your 3D planes. A pure matter of extra reduction and larger prop disk, with reduced vortex flow losses. But at the price of lower speeds. It all is a trade-off.